Vulnerability in Mozilla Firefox for iOS (July 7, 2026)

unknownCVE-2026-13356

A vulnerability has been discovered in Mozilla Firefox for iOS. It allows an attacker to bypass the security policy.

CSIRTS triage

vendor: Mozilla product: Firefox for iOS Authentication bypass

What: A vulnerability allows bypassing the security policy.
Who is affected: Users of Mozilla Firefox for iOS are affected.
Urgency: Remediation is urgent due to the potential for exploitation.
Action: Update Firefox for iOS to the latest version to mitigate the issue.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: CERT-FR Avis de sécurité (FR · national-cert · site)
Severity: unknown
Published: 2026-07-07
Exploitation: Not in CISA KEV at last sync
Language: Machine-translated to English — verify against the original

Original advisory: https://www.cert.ssi.gouv.fr/avis/CERTFR-2026-AVI-0839/

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-133560.22% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 12% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-13356	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

Recent advisories for Mozilla Firefox for

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

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